/* -*- Mode: C; c-basic-offset:4 ; -*- */
/*
 *  (C) 2001 by Argonne National Laboratory.
 *      See COPYRIGHT in top-level directory.
 */

/** Contended RMA put/get test -- James Dinan <dinan@mcs.anl.gov>
  *
  * Each process issues COUNT put and get operations to non-overlapping
  * locations on every other processs.
  */

#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include "mpi.h"

#define MAXELEMS      6400
#define COUNT         1000

static int me, nproc;
static const int verbose = 0;

void test_put(void);
void test_put(void)
{
  MPI_Win  dst_win;
  double  *dst_buf;
  double   src_buf[MAXELEMS];
  int      i, j;

  MPI_Alloc_mem(sizeof(double)*nproc*MAXELEMS, MPI_INFO_NULL, &dst_buf);
  MPI_Win_create(dst_buf, sizeof(double)*nproc*MAXELEMS, 1, MPI_INFO_NULL, MPI_COMM_WORLD, &dst_win);

  for (i = 0; i < MAXELEMS; i++)
    src_buf[i] = me + 1.0;

  MPI_Win_lock(MPI_LOCK_EXCLUSIVE, me, 0, dst_win);

  for (i = 0; i < nproc*MAXELEMS; i++)
    dst_buf[i] = 0.0;

  MPI_Win_unlock(me, dst_win);

  MPI_Barrier(MPI_COMM_WORLD);

  for(i = 0; i < nproc; i++) {
    int target = i;

    for(j = 0; j < COUNT; j++) {
      if (verbose) printf("%2d -> %2d [%2d]\n", me, target, j); 
      MPI_Win_lock(MPI_LOCK_EXCLUSIVE, target, 0, dst_win);
      MPI_Put(&src_buf[j], sizeof(double), MPI_BYTE, target, (me*MAXELEMS+j)*sizeof(double), sizeof(double), MPI_BYTE, dst_win);
      MPI_Win_unlock(target, dst_win);
    }

    for(j = 0; j < COUNT; j++) {
      if (verbose) printf("%2d <- %2d [%2d]\n", me, target, j); 
      MPI_Win_lock(MPI_LOCK_EXCLUSIVE, target, 0, dst_win);
      MPI_Get(&src_buf[j], sizeof(double), MPI_BYTE, target, (me*MAXELEMS+j)*sizeof(double), sizeof(double), MPI_BYTE, dst_win);
      MPI_Win_unlock(target, dst_win);
    }
  }

  MPI_Barrier(MPI_COMM_WORLD);

  MPI_Win_free(&dst_win);
  MPI_Free_mem(dst_buf);
}


int main(int argc, char* argv[]) {
  MPI_Init(&argc, &argv);
  MPI_Comm_size(MPI_COMM_WORLD, &nproc);
  MPI_Comm_rank(MPI_COMM_WORLD, &me);

  assert(COUNT <= MAXELEMS);

  if (me == 0 && verbose) {
    printf("Test starting on %d processes\n", nproc); 
    fflush(stdout);
  }

  test_put();

  MPI_Barrier(MPI_COMM_WORLD);

  MPI_Finalize();

  if (me == 0 && verbose) {
    printf("Test completed.\n");
    fflush(stdout);
  }

  if (me == 0)
    printf(" No Errors\n");

  return 0;
}
